1. Field of the Invention
The present invention relates to a display method and apparatus, and more particularly to a display method and apparatus which can control the brightness of a light source provided in a micro projector.
2. Description of the Related Art
During a conference or a presentation, a projector is often used to convert an image signal received from an image supply device, such as a computer, into projection light and to project the light onto a screen or a white board. Such a projector may be provided with a transmissive Liquid Crystal Display (LCD), a reflective LCD, a Digital Micromirror Device (DMD), and a light source, and projects an image to be displayed by representing in grayscale through control of an alignment angle of liquid crystals provided in the LCD, or adjustment of an on/off time of the DMD, and by simultaneously controlling the light source. The projector requires large amounts of electric power, and generates a great amount of heat due to the power consumption. Accordingly, extensive research is being conducted into reducing the power consumption of a projector. Particularly, in the case of applying a projector to a portable terminal, the power consumption of 1˜2 Watts exerts a fatal influence upon the heat generation.
In the case of a Liquid Crystal Display having an LCD panel and a backlight as a light source, a method for adjusting the luminance of the backlight and the luminance of the LCD panel, which are correlated with each other, after analyzing values of red, green, and blue color components of pixels of the display data, has been used. Specifically, according to this method, the luminance of the backlight and the luminance of the LCD panel are adjusted based on the maximum grayscale value that is confirmed by computing a luminance (Y) signal, or based on the maximum grayscale value having the largest value among the confirmed maximum grayscale values of Red (R), Green (G), and Blue (B) colors.
Although the method of adjusting the luminance of the backlight and the luminance of the LCD panel of the Liquid Crystal Display can be applied to a projector, use of the maximum grayscale value of the luminance (Y) signal may cause data loss in the actual RGB signals to generate color errors. Also, in the case of using the maximum grayscale value having the largest value among the maximum grayscale values of RGB colors, only the maximum grayscale value is used, and thus in the case of an image having severe monochromaticity among RGB colors, the maximum grayscale value approaches the threshold grayscale value (e.g. 255) to result in almost no power saving effect on the projection.
Accordingly, there is a need for schemes for reducing the power consumption and the amount of heat generated in driving the light source.